Downy Mildew

Source: Gary Bergstrom, Cornell University

Source: Ken Wise, Cornell University

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Peronospora manshurica
Downy mildew is very common and widespread throughout NY, and can often be found in most soybean production fields each year. Symptoms include pale green to bright yellow spots appearing first, which will eventually become necrotic spots. During humid conditions, sporulation may be observed at these spots on the lower leaf surface. It is not considered a disease of economic importance in NY, and therefore requires no management recommendations.